A demonstrator gives the peace sign as the Women's March on Washington makes its way down Pennsylvania Avenue on January 21, 2017 in Washington, DC. (Zach Gibson / Agence France-Presse)

Demonstrators chant during the Women's March on Washington January 21, 2017 in Washington, DC. (Zach Gibson / Agence France- Presse)

Law enforcement officers hold candles during a candlelight vigil on the National Mall Saturday, May 13, 2017 in Washington, D.C. The 29th annual vigil took place during National Police Week and honored law enforcement officers who have fallen in the line of duty. (Zach Gibson/The Dallas Morning News)

Demonstrators hold an American Flag during a protest on January 29, 2017 in Washington, D.C. Protestors in Washington and around the country gathered to protest President Donald Trump's executive order banning citizens of Iraq, Syria, Iran, Sudan, Libya, Somalia or Yemen from traveling to the United States. (Zach Gibson / Getty Images)

Demonstrators chant near the Washington Monument during a protest in Washington on January 29, 2017 in Washington, D.C. Protestors in Washington and around the country gathered to protest President Donald Trump's executive order banning citizens of Iraq, Syria, Iran, Sudan, Libya, Somalia or Yemen from traveling to the United States. (Photo by Zach Gibson/Getty Images)

Members of the Franciscan Friars Minor of Fort Wayne, IN, gather outside of The U.S. Supreme Court during the 44th annual March for Life January 27, 2017 in Washington, DC. This year marks the 44th anniversary of Roe v. Wade, the Supreme Court case that established a woman's right to abortion. (Zach Gibson / Agence France-Presse)

A helicopter flies over a protest reacting to the inauguration of President-elect Donald Trump January 20, 2017 in Washington, DC.

U.S. Air Force Academy graduates salute as The National Anthem is played during the U.S. Air Force Academy Commencement Ceremony at the U.S. Air Force Academy in Colorado Springs, Co., on Wednesday, June 1, 2016. (Photo by Zach Gibson / The New York Times)

Flowers left by mourners sit in front the U.S. Supreme Court Building following the death of Supreme Court Justice Antonin Scalia on February 14, 2017, in Washington, D.C. (Zach Gibson / The New York Times)

Demonstrators march down Pennsylvania Avenue during the People's Climate March in Washington, D.C., U.S., on Saturday, April 29, 2017. (Zach Gibson / Bloomberg)

Demonstrators participate in a 'die-in' in front of the White House on January 27, 2017 in Washington, DC. Anti-abortion activists are gathering for the 44th annual March for Life in Washington, protesting the 1973 Supreme Court decision legalizing abortion. (Zach Gibson / Agence France-Presse)

Texas law enforcement officers stand on the West Lawn of The U.S. Capitol Building as names are read during a roll call of fallen officers during the 36th Annual National Peace Officers' Memorial Service on Monday, May 15, 2017 in Washington, D.C. The service, which takes place every year on May 15, honored federal, state, and local officers killed or disabled in the line of duty. (Zach Gibson/The Dallas Morning News)

A Trump supporter waves an American Flag near The National Mall during the inauguration of President-elect Donald Trump January 20, 2017 in Washington, DC.

Riley Harris and Julie Hansen, at left, hug as protestors gather on the ellipse during the Women's March on Washington, on January 21, 2017, in Washington, D.C.

Abortion opponents walk on Constitution Avenue towards The Supreme Court of the United States during the 44th annual March for Life January 27, 2017 in Washington, DC. This year marks the 44th anniversary of Roe v. Wade, the Supreme Court case that established a woman's right to abortion.

A man takes pictures from atop a bus stop awning as police officer form a line while a limousine burns on K Street during a protest in response to the inauguration of President Donald Trump in Washington, D.C., on January 20, 2017. (Zach Gibson / Agence France-Presse)

Demonstrators lock arms while marching to Capitol Hill from The White House during a protest in response to the fatal police shootings of Alton Sterling and Philando Castile on July 7, 2016, in Washington, D.C. (Zach Gibson / Getty Images)

A demonstrator waves a Corporate States of America flag outside of the Eisenhower Executive Office Building in Washington, D.C. on November16, 2015.

People watch the third presidential debate between US Democratic presidential candidate Hillary Clinton and US Republican presidential candidate Donald Trump is pictured at The Hawk 'n' Dove bar October 19, 2016 in Washington, D.C. (Zach Gibson / Agence France-Presse)

TV news assistants sprint out of the U.S. Supreme Court following the court's decision in favor of same sex marriage in Washington D.C., on Friday, June 26, 2015. (Zach Gibson / The New York Times)

Demonstrators gather on Capitol Hill after marching from The White House during a protest in response to the fatal police shootings of Alton Sterling and Philando Castile on July 7, 2016, in Washington, D.C. (Zach Gibson / Getty Images)

Demonstrators carry American flags during the March for Truth Rally at The Washington Monument in Washington, D.C., U.S., on Saturday, June 3, 2017. The march called for the appointment of a special prosecutor to investigate accusations of the Trump Administration's ties to Russia. (Zach Gibson / Bloomberg)

Vin Testa of Washington D.C. waves a flag following the Supreme Court's decision in favor of same sex marriage in front of the U.S. Supreme Court in Washington D.C., on Friday, June 26, 2015. (Photo by Zach Gibson / The New York Times)

Cornel West speaks during a press conference calling for Congress and the U.S. Department of Justice to launch a federal investigation into the hiring and promoting practices of United Airlines at The National Press Club on September 15, 2016, in Washington, D.C.

Andrea Ortiz, left, and Courtney Hunt, right, both of D.C., hold candles during a vigil honoring victims of the shooting in Orlando at Dupont Circle in Washington, D.C. on Monday, June 13, 2016. (Photo by Zach Gibson / The New York Times)

Demonstrators gather in front of the Trump International Hotel Washington on January 29, 2017 in Washington, D.C. Protestors in Washington and around the country gathered to protest President Donald Trump's executive order banning citizens of Iraq, Syria, Iran, Sudan, Libya, Somalia or Yemen from traveling to the United States. (Photo by Zach Gibson/Getty Images)

An inflatable replica of a nuclear weapon stands in McPherson Square during a Global Zero rally urging the elimination of nuclear weapons in Washington, D.C., on Friday, April 1, 2016. (Photo by Zach Gibson / The New York Times)

Supporters of Virginia's same-sex marriage ban hold a rally in front of the 4th U.S. Circuit Court of Appeals before a court hearing May 13, 2014 in Richmond, Virginia. Three judges from the U.S. 4th Circuit Court of Appeals heard arguments from both sides of the case that seeks to determine whether Virginia's same sex marriage ban is constitutional.

Members of the antiwar group CodePink participate in a Hoops not Bombs rally encouraging peace in Iran on August 4, 2017, in Washington, D.C. (Zach Gibson / The New York Times)

Flint resident Jada Williams watches a House Oversight and Government Reform Committee hearing Examining Federal Administration of the Safe Drinking Water Act in Flint from an overflow room on Capitol Hill in Washington D.C, on Thursday, March 17, 2016.. (Photo by Zach Gibson / The New York Times)

U.S. Capitol Police stand guard during Democracy Awakening's Congress of Conscience Day of Action in Washington, D.C. on Monday, April 18, 2016. (Photo by Zach Gibson / The New York Times)

Signs supporting Republican Presidential Candidate Donald Trump and Ed Tinus, a Maryland candidate for the U.S. Senate, sit in the back of a car outside of a Trump rally at Stephen Decatur High School in Berlin, Md., on Wednesday, April 20, 2016. (Photo by Zach Gibson / The New York Times)